Space Earth Science in Space Age

Space conquest not only allowed mankind to the far reaches of our solar system or to Moon. It brought a lot to Earth science too. As aeronautics and first rocketry already had brought the ability to see Earth from atop, observation satellites increased this ability. For the first time, planet Earth could be seen in its entirety. Atmosphere, continents, and oceans progressively came to be seen as interacting systems. Earth is now becoming a comprehensive object of space science. Earth observation has always been closely coupled to information technology development as a revolution occurred which enabled scientists to deal with huge amounts of data on desktop computers

->see a perspective diagram of NASA Earth science programs 1958-now (with Earth science missions also available at the ESA program list)

the first image taken on April 1, 1960 by TIROS 1, which was the first television picture of Earth from space. picture courtesy NASA

As far as USA are concerned, first Earth missions assigned to spacecraft until the mid-60s were weather. NASA learned to put satellites exactly where they had to be and to keep them there. As far as the weather forecast was concerned, the first U.S. meteorological, polar-orbiting satellite was the TIROS-1 (or Television Infrared Observation Satellite), which weighed 270 pounds and carried two cameras and two video recorders, starting a policy of interagency collaborations. It launched by April 1960. NASA managed the program with help from the U.S. Army Signal Research and Development Lab at Ft. Monmouth, Radio Corporation of America (RCA), the U.S. Weather Bureau (now the National Weather Service) and the U.S. Naval Photographic Interpretation Center. Throughout the 1960s, 10 TIROS satellites in total carried increasingly advanced instruments and technology. By 1965, meteorologists combined 450 TIROS images into the first global view of the world's weather. The TIROS 1 was designed to test the feasibility of obtaining and using TV cloudcover pictures from satellites. The TIROS Program was NASA's first experimental step to determine if satellites could be useful in the study of the Earth. At that time, the effectiveness of satellite observations was still unproven. The TIROS Program's first priority was the development of a meteorological satellite information system. Weather forecasting was deemed the most promising application of space-based observations as TIROS began continuous coverage of the Earth's weather in 1962, and was used by meteorologists worldwide. Named after the Latin word for rain cloud, the Nimbus satellites were a series of seven Earth-observation satellites launched over a 14-year time period from 1964 to 1978, and instrumental into the development of Earth science. In total, the satellites provided Earth observations for 30 years. Verner E. Suomi is considered the 'father of satellite meteorology' in the USA as he pioneered remote sensing of Earth from satellites in polar orbits with Explorer 7 in 1959 and geostationary orbits with ATS-1 in 1966. He was best known for his invention of the 'spin-scan' camera which enabled geostationary weather satellites to continuously image Earth, yielding the satellite pictures commonly used on television weather broadcasts. Suomi spent nearly his entire career at the University of Wisconsin-Madison, where in 1965 he founded the university's Space Science and Engineering Center with funding from NASA. The center is known for Earth-observing satellite research and development. In 1964, Suomi served as chief scientist of the U.S. Weather Bureau for one year. He died in 1995 at the age of 79. The TIROS kept their career and eventually ended like the NOAA satellites, the last of which launched by February 2009. Since 1975, the GOES (Geostationary Operational Environmental Satellite) satellites are able to orbit in synchronization with Earth's rotation as their data combined with those of some GOES polar-orbiting satellites are giving powerful tools to meteorological forecasters. The NOAA, for example, is nowadays collaborating with the European Organisation for the Exploitation of Meteorological Satellites. Since Feb. 1, 2010, the White House restructured the National Polar-orbiting Operational Environmental Satellite System, or NPOESS, tri-agency effort among NOAA, NASA and the Department of Defense, as the NPOESS Preparatory Project, scheduled to launch in late 2011, is to test the capabilities of next-generation sensors and provide continuity with NASA's Earth Observing System satellites. Two more polar satellites will launch under the Joint Polar Satellite System by 2015 and 2018, or NOAA and NASA also are working to launch the next generation GOES-R series of satellites, beginning in 2015. These spacecraft will have twice the clarity of today's GOES and provide more than 20 times the information. Sixty years ago, scientists were unsure whether Earth’s surface could be seen clearly from space. Many thought that the dust particles and other aerosols in the atmosphere would scatter the light, masking the oceans and continents. The Gemini and Apollo programs demonstrated otherwise. Astronauts used specialized cameras to take pictures of Earth that show the beauty and complexity of our living planet, and helped kickstart the era of Earth science research from space. In 1972, the first Landsat mission began its 45-year record of ocean and land cover as since the fall of 1997, NASA satellites, since the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite, have continuously and globally observed all plant life at the surface of the land and ocean. The decade 1968-1977 had NASA expand the number of Earth science satellites and above all build a vast array of programs at Earth to interpret data returned. On another hand, weather did not remain the sole purpose of satellites. They became used for other purposes like Earth's atmosphere studies, or more comprehensive science using a wide range of new imaging techniques like the infrared. The National Oceanographic and Atmospheric Administration (NOAA) was created during this period, in 1974, taking under its umbrella various federal weather and climate services which had been combined into the National Weather Service in 1970

->More About the NOAA GOES Workhorse Program!
The GOES program formally began in 1975 as a joint effort of NOAA and NASA. The GOES series of U.S. satellites are developed by a joint NASA-NOAA-Industry partnership, launched by NASA (with industry partners), and operated by NOAA. NOAA operates a GOES-East satellite and a GOES-West satellite to provide constant vigil for the atmospheric triggers" for severe weather conditions like tornadoes, flash floods, hail storms, and hurricanes. GOES-West covers the western U.S. and the Central and Eastern Pacific Ocean. GOES-East covers the eastern U.S. and the Atlantic Ocean. The GOES ground station is located at Wallops, with the Goddard station, known as the Wallops Backup (WBU), at NASA's Goddard able to operate the GOES East is capable of operating one GOES satellite, specifically the GOES East satellite operating over the Atlantic Ocean. A new 54-foot antenna at Wallops was designed to operate through a Category 3 hurricane as it can survive a Category 5 hurricane. The antenna both are transmitters for sending commands to the satellites, and receivers for collecting information from. On October 16, 1975, the first satellite under the GOES program was launched from Cape Canaveral, Florida. A next gen series of GOES weather satellites financed by NASA and the NOAA will replace the current fleet, which had not been modernized since 40 years

an edited picture of the Great Lakes in Northern America as seen from space. picture courtesy NASA/JPL

Earth science began to come out of age in 1978-1987. Weather and atmospheric tools grew further. The ozone layer hole was discovered as remote sensing satellites became one of NASA's first foci. Once Earth space science definitively mature it became an official part of NASA's activities during the decade 1987-1998. It took the name of "NASA's Mission to Planet Earth". Due to the information age, focus shifted from data collection to data sharing. Miscellaneous data were made available, or real-time views of our environment provided. Data Acquisition Centers, or DAACs, served as clearing houses for processed satellite data. Earth science was the subject of the first Web page ever created by NASA. Earth science missions and programs are still keeping on today and are aiming at providing more details about how the Earth system is working

The Earth Observing System Data and Information System (EOSDIS) is collecting environmental data from more than 30 satellites and making it available to more than 17,000 users, from U.S. federal or local researchers to the general public. The EOSDIS is located at the Goddard Space Flight Center (GSFC) in Greenbelt, Maryland. NASA's Earth Observatory, a NASA website which displays images taken by Earth science satellites to the general public, was created in April 1999. A constantly orbiting fleet of NASA satellites keeps its sensors trained on our blue planet –capturing the intricacies of its atmosphere, the seasonal cycles of plant growth and sea ice, and the patterns in ocean circulation and temperature. As NASA's Earth science data system, EOSDIS provides command and control, scheduling, data processing, and data archiving and distribution services. EOSDIS manages this flow of information – from satellites in space to data processing facilities to a scientist's desktop – with a network of 12 Earth science data centers in the U.S. These Earth science data centers are located at NASA centers or partner institutions and specialize in specific types of datasets, such as snow and ice, atmospheric or ocean data. NASA assets in terms of Earth science satellites currently are mostly part of the agency's Earth Observing System (EOS) which is a set of satellites devised to make long-term, comprehensive measurements of Earth's interrelated systems. The EOS began by 1995. The EOS fleet has revolutionized understanding of how our planet works by helping pioneer an interdisciplinary approach to Earth science. This approach, called Earth systems sciences, focuses on understanding the many components of Earth as an interconnected system rather than as independent parts. New day thermal sensors names QWIPs, for Quantum Well Infrared Photodetectors, have been deviced in the perspective of Earth science and used aboard the Landsat satellites series since about 2012 on the complex principles of quantum mechanics. Gallium arsenide semiconductor chips trap electrons in an energy state 'well' until the electrons are elevated to a higher state by thermal infrared light of a certain wavelength. The elevated electrons create an electrical signal that can be read out and recorded to create a digital image. Recently, space missions have been able to improve their monitoring skills in terms of agriculture. Zone maps compiled with data from remote-sensing instruments including NASA and the USGS's Landsat satellites are able to tell farmers about the state of their current fields. Maps may help, for example, to adjust his fertilizer use—apply, or showing the difference between healthy and stressed plants by representing the amount of light they're reflecting in different bands of the electromagnetic spectrum. Scientists, insurance agents, water managers, foresters, mapmakers, and many other types of users are provided with such a useful information

Since its completion by 2010, the International Space Station (ISS) is hosting a series of Earth science tools, as the 'Cupola' is also found on board, a kiosque with cameras allowing to images of the Eearth

->The Landsat Program
A well-known program of Earth science from space is the series of the Landsat satellites. The first satellite in the program, ERTS-1, was launched on July 23, 1972 by NASA in cooperation with the Interior Department and its science agency, the U.S. Geological Survey. As ERTS being a awkward thing to say, the ERTS-1 satellite was rechristened Landsat 1. As soon as by the 1970's, scientists working on the Large Area Crop Inventory Experiment demonstrated that crops could be monitored worldwide from space, and in 1979 it was used to accurately assess total yield of the Soviet wheat crop before the harvest. Crop monitoring thus come to be available to worldwide food estimates, government policies and international trading decisions. By 1979 the Carter administration transferred the Landsat program to the National Oceanic and Atmospheric Administration (NOAA) and transition it from a research program to an operational one as in 1984 the U.S. Congress passed a law commercializing the program into the Earth Observation Satellite Company (EOSAT). EOSAT however took over in an environment where the prices for Landsat images had driven away all but the largest customers, such as the military and oil and mining companies. Also during the EOSAT tenure, image acquisitions became customer-driven, resulting in limited global coverage and thus the utility of the data collection declined. Landsat funding was then contributed by other agencies as the U.S. Congress in 1992 returned operation of the program to the government. Landsat satellites were workhorses with a long life timespan as the Landsat 8 (Landsat Data Continuity Mission (LDCM)) launched by 2013 since provided twice as many images as Landsat 7. Since 2008, all the data in the USGS archive captured from the Landsat satellites are distributed by the USGS to users over the Internet for free. Now well over three million images are in the Landsat archives, and more imagery is added every day representing the surface of Earth over a 40-year period. Since 2012 a high-performance computing and data access facility further, called NASA Earth Exchange (NEX) has been set which combines Earth-system modeling, remote-sensing data from NASA and other agencies, and a scientific social networking platform to deliver a complete research environment to scientists based upon Landsat imagery. In terms of instrumentation, the original plan was to rely on special television cameras called 'return beam vidicons,' (RBV) to do the imaging. Hughes Aircraft then introduced a scanner system that imaged the Earth in strips having a wider range of wavebands, using the then-relatively new technology of fiber optics, allowing for discriminatory sensing. Landsat sensors kept improving over time. The Landsat program is now jointly managed by NASA and the Interior Department, the U.S. Geological Survey specifically. The longest lasting satellite in the program was Landsat 5, which worked during 28 years and 10 months since March 1984. It completed over 150,000 orbits and sent back more than 2.5 million images of Earth’s surface and was to be decommissioned early 2013 after the failure of a redundant gyroscope. Originally designed to be retrievable by the space shuttle, Landsat 5 was equipped with extra fuel which kept it operating for much longer than anticipated after the space shuttle retrieval plan was thrown out. Albeit facing more than twenty technical issues, the USGS Flight Operations team found engineering and operational fixes to work those around, which included losing batteries, star trackers, and on-board data recording capability. The satellite's 12-year longevity preserved the Landsat program through the loss of Landsat 6 in 1993, preventing the specter of a data gap before the launch of Landsat 7 in 1999. Each Landsat carried two instruments, the Multispectral Scanner System (MSS) and the Thematic Mapper (TM) as the latest Landsat will carry two new instruments, the Operational Land Imager and the Thermal Infrared Sensor, which will collect data that are compatible with data from Landsat 5 and 7, and improve upon it with advanced instrument designs that are more sensitive to changes to the land. In terms of attitude control Landsats are carrying three gyroscopes, of which two only are used to maintain control

->What the STRM Mission Was
On Feb. 11, 2000, two radar antennas built by JPL launched aboard Space Shuttle Endeavour on an 11-day mission named the 'Shuttle Radar Topography Mission.'. They performed the first-ever near-global high-resolution database of the Earth's topography, collecting topographic data over nearly 80 percent of Earth's land surfaces, and radar allowing to previously obscured regions by persistent cloudiness. The data benefited scientists, engineers, government agencies or the public, with such applications ranging from land-use planning to virtual Earth exploration. NASA is currently using STRM data to create an even better global topographic map as it combines them with the more complete Advanced Spaceborne Thermal Emission and Reflection Radiometer global digital elevation model of Earth, which was jointly released in 2009 by NASA and Japan's Ministry of Economy, Trade and Industry

->ESA's Meteosat Program
Drum-shaped Meteosat-1, ESA’s first Earth observation satellite was launched on 23 November 1977, providing a coverage of the whole globe from geostationary orbit. The Meteosat-1 was a important milestone in European cooperation in space as individual countries had pioneered monitoring of the ionosphere from space and the European Space Conferences of the 1960's agreed in principle that there should be a European weather satellite. Meteosat was initiated as a French project, with involvement both from CNES and the French meteorological service. At the same time, the European Space Research Organisation (ESRO, a forerunner of ESA) was considering possibilities for polar-orbiting and geostationary satellites, ESRO deciding on a geostationary satellite. To avoid a duplication with the French endeavour, and after a long period of fact-finding and negotiation, the foundations were laid for the Meteosat project to evolve from a French one to a European one. Rather than uproot the whole operation from France, it was decided to establish an ESA office in Toulouse, from where Meteosat could be developed and guided. Meteosat-1 hovered above the Greenwich meridian as it featured a water vapour channel to track the motion of moisture in the air. The satellite could scan Earth’s full disc every 30 minutes, with the data being provided in near-real time to users. The new satellite required great improvements in ESA’s computing power both for telemetry and for image data processing. 35 years worth of Meteosat imagery are now available online as provided by the successors in the Meteosat program. There was a gap of almost a decade between the launch of Meteosat-1 and the official founding of Eumetsat, the European organisation created to exploit satellite data for weather and climate research. Eumetsat nowadays owns 30 member states and its keeps developing new satellite programmes in cooperation with ESA. A Meteosat Second Generation followed as currently a Meteosat Third Generation is being developed pushing Europe until in the 2030's